This invention relates to a power switch assembly and more particularly to improvements in both a power switch assembly comprising a circuit breaker and a circuit disconnector, and a power switch assembly comprising a lightning arrester, a circuit breaker and a circuit disconnector.
A conventional power switch assembly has typically comprised a circuit breaker and a circuit disconnector each mounted separately and electrically connected to each other by copper or aluminum conductors. The disconnector has consisted of a first and a second supporting porcelain insulator disposed at both ends of a horizontal supporting base with a stationary contactor, and line-receiving terminal mounted atop the first supporting insulator, and a movable, rod-shaped contactor supported by the second porcelain insulator and operably connected to a disconnector driving mechanism mounted atop a driving porcelain insulator which is disposed linearly at a predetermined distance between the first and second supporting insulators. This driving porcelain insulator is driven by a driving source through a driving mechanism to cause the movable contactor to engage with and disengage from the stationary contactor.
Also, the circuit breaker has been disposed apart from that side of the supporting base having the second porcelain insulator. The circuit breaker has comprised an operating mechanism disposed on a floor or the ground, a supporting porcelain insulator vertically disposed on the operating mechanism, and a porcelain clad main body of the circuit breaker mounted atop the supporting porcelain insulator having one terminal interposed therebetween. The main body of the circuit breaker has been connected at the one terminal to the movable contactor through a connecting lead and the other terminal has been connected to a feed line.
There is also known another power switch assembly comprising, in addition to the circuit breaker and disconnector as described above, a lightning arrester. The lightning arrester has typically been vertically disposed on a separate horizontal supporting base located on that side of the first-mentioned supporting base remote from the circuit breaker with a certain spacing formed therebetween. This lightning arrester has typically included a terminal located at the upper end thereof which is connected to the receiving line and via a connecting lead to the terminal of the circuit disconnector disposed on the first supporting porcelain insulator. The lightning arrester, the circuit disconnector and the circuit breaker are aligned with and spaced from one another.
In the last-mentioned power switch assembly, the lightning arrester, the circuit disconnector and the circuit breaker have been separately installed on a floor or the ground. Thus, it has been required to maintain a predetermined electrically insulating spatial distance between an electrically charged or grounded portion of each of the lightning arrester, the circuit disconnector and the circuit breaker and grounded or an electrically charged portion of an adjacent one thereof respectively. This has resulted in an increase in floor area required for the power switch assembly to be installed.
On the other hand, the first-mentioned power switch assembly is generally so large-scaled that the same is installed on a floor or the ground by several persons. Thus, in order to easily effect both the installation of the circuit disconnector, and circuit breaker and the electrical connection of the circuit disconnector to the one terminal of the circuit breaker, it has been a common practice to sufficiently space the circuit from the circuit breaker.
Furthermore, with the increased utilization of gas insulated switch assemblies comprising the circuit disconnector and breaker accommodated in a single gas filled container, developments of move compact power switch assemblies comprising the circuit disconnector and breaker formed independently of each other have also been required to compete with the gas insulated switch assembly. This requirement can be met by power switch assemblies comprising the circuit disconnector and breaker as described above arranged close to each other thereby to decrease a distance therebetween. This measure has resulted in an objection that an electrically insulating spatial distance cannot be maintained between the circuit disconnector and breaker because of a decrease in each of distances between the supporting base put at a ground potential for the circuit disconnector and the one terminal put at a high potential of the circuit breaker and between a driving mechanism of the circuit disconnector and the other terminal of the circuit breaker brought into different potentials upon the opening of the circuit breaker. Thus, it is actually impossible to so decrease the distance between the circuit disconnector and breaker resulting in a fairly broard space necessarily being left therebetween.
Accordingly, it is an object of the present invention to provide a new and improved power switch assembly comprising a circuit breaker and a circuit disconnector installed in a small floor area with electrically insulating spatial distances satisfactorily maintained among the components put at different potentials and affording easier installation and electrical connection while having a sufficiently simple construction to be inexpensive and easily transported.
It is another object of the present invention to provide a new and improved power switch assembly comprising a circuit breaker, and a circuit disconnector and a lightning arrester installed in a small floor area with an electrically insulating spatial distance satisfactorily maintained between adjacent ones thereof while having a sufficiently simple construction to be inexpensive and easily transported.